Latch tripping mechanism



4 Sheets-Sheet l Wom Q Nu hwmew awe/Mom f/VGH IA .SFA/FORO,

May 25, 1948. H. w. SANFORD I LATCH DRIPPING MECHANISM Filed Jan. 20,1943 May 251, 1948. w, n' v 2,441,978

LATCH TRIPPING MECHANISM Filed Jan. 20, 1943 4 Sheets-Sheet 2 May 25,1948. H/w. SANFORD 2, 8

LATCH TRIPPING' MECHANISM Filed Jan. 20, 1943 v 4 Sheets-Sheet 3 May 25,1948. H. w. SANFORD LATCH TRIPPING MECHANISM Filed Jan. 20, 1943 4Sheets-Sheet 4 Patented May 25, 1948 jUNlTED STATES PATENT; OFFICE v i vLATCH :rrnrrnve MECHANISM Hugh W, Sanford, Knoxville, Tenn, assignor toThe Sanford Investment Company, Wilmington, Del., a corporation ofDelaware. Application January 20, 1943, Serial No. 473,013

the like, particularly such as employ mine cars,

provision is made. for the automatic dumping of such conveyors byreleasing the drop bottom doors when theconveyor reaches the bin orother point .ofdischarge. ,It has been customary and desirable for aseries of drop bottom doors to be interconnectedfor successivedroppingin 12-3 order from front to rear of the car when the car:reachesthe point of dumping,

This has been accomplished usually by supporting atiree edge of aforward door upon a hinged edge'of the; next :rearward door in suchmanner that the'opening .of the latter will relea'seia'utomaticallytheforward door for dropping. The rearmost door of thecarhasit's freeedgesupported by latch means adapted to be released'when the car reachesthe point of dumping.

Such automatic cars as generally used heretofore haverequired latchbarmechanism located outside the car for controlling the dropping ofthedoors. Such latch bar mechanism has been objectionable and expensive.

I have set forth in my prior application on Door latch mechanism, Ser.No. 432,341, Patent No. 2,399,708, improved latch mechanismsforcontrolling the release of the doors. 1

, The object of this invention is to improve'the construction; of thetripping mechanism for the door; latches,ito facilitate the release ofthe -latches by mechanism having improved characteristics, whileenclosing the latches in protected positionso'n the car.

I haveshown the invention in several modified ,iorms inthe accompanyingdrawings, in which:

,- 1 is a side elevation of a mine car and track, showing latches of thecharacter here used;

; Fig. 2 is'an' enlargedside elevation-of an end portion of the car,showing one form of tripping device;

;',Fig. 3 is a diagrammatic view of aportion of -the car and showing thetripping device in one pos ion;

4.-is a similar-view showing the tripping device-in' another position 18Claims. (01. 21458) Fig. 5 is a diagrammatic end elevation, in sectiontherethrough; n

Fig. 6 is an end elevation of the control switch partly for the trippingdevice;

Fig. '7 is a side elevation thereof; and

Fig. 8 is a diagrammatic view from the side of the car showing amodified form-of tripping device. 7

The invention is shown as applied to a drop bottom mine car adapted forthe conveying of coal or other loose vlading from areceiving point to apit or other point of discharge: The mine car is shown generally ofthetype set forth, for instance, in my prior patent} No. 2,001,471, grantedMay 14, 1935, representing a four-wheel mine car having three dropbottom doors, adapted to travel on a track formed bya pair of railsdesignated generallyR .L v c The general structure of the car comprisesside and end walls I and 2, respectively, the side walls I rising from apair of oppositely disposed side sills 3 connected together at the endsof the car by means of combined end-sills and bumpers the adjacent axle6.

' The car is shown as of thecharacterprovided with three drop bottomdoors adapted for discharge in 1,-23 order from front torearof the car,which doors are designated respectively [0, II and [2, The forward doorI0 is pivotally supported on a hinge rod J3, while each ofthe middle andrear doors H and, I2 is slidably and pivotally mounted. on a hinge rodl4, extending between opposed boxes,.with the extreme forward edge ofsaid door projecting laterally from the hinge rod and arranged tosupport the free edge vof the next forward ,door. 7 Thus upon release ofthe rear door it may, drop suificient to drag and move bodily rearward,thereby'releasingithe free edge of the middle door which will likewisemove downward and rearward releasing the freeedge of the forward 'door..This occurs usually just before the car reaohesthe' bin and permitsdropping of the forward, door forpdischarge of the lading as-soon as.room enough is provided in the bin therebeneath, the otherfdoorsdropping in succession during forward movement of the car over the bin,in 123 order from front to rear of the car.

After dumping in passing over the bin, the doors are adapted to beclosed by the usual doorclosing rails located in the track, said doorshaving indentations I to ride thereon, which successively-svving theminto their closed positions. The doors may be pushed forward'intotightly engaged supporting positions by wedge blocks having upwardly andforwardly inclined front faces in position for. engagementhy?lugstattachedv to the free edge of the rearward door I2 and projectingtherefrom, as set'forth mpre fully in my prior Patent No.2,0013471grantedMayl l, 1935.

As shown in Figs. 1 to 5, provisioniisimadeior latching the free edge ofthe rearward .door .I2.

for thereby holding the. doors I0, II and"'i2'in their closed positions,retaining the lading in the ing. For this purpose latches iiiare-provided adjacent the-rear end'of=the" carpivotally sup-" *Each'ofthe'latches-has a conoave-seat -2ll formed therein in position to engagea trunnion ZI attached to thefree edgefof-the' rearward door I2 to*support 'said' rearward "door. As shown in Fig.8; the seat 20 islocated on the opposite-side of the vertical "planepassing through theaxis of the'shaft I 9 from the door I2, so that the weight ':of thedoorandthe' 'la'ding thereontendsto'maintain'. the"latched relationwithout anytendency for this "wei'ghtito "push' the l atch" to one side.This'is particularly true becauseof the concave shape of the seat 20engagedby'theconveirend oit'he .trunnioni' I whereby-anymovementof the:latchi'tendin'gto'releasdthe door must flrst raise upthe' free'e'dge'bf thedoor.

Each offthe ilat'ches I 8' has afl'at'eralfpin"2 2" at-- tached"theretoiaridi'projecting through a' slot- 23 in theleidjacentipor'tionof the ende'sill '4; sothatia lever can be 'insertedfove'r saidsill,'beneath the pin-22; fori'the'manu'alrelease of said latch.

I "A coiled spring"245 is iinterposed'fbetween"the. finneri face .of theend 'sill 4"an'd"lthe1atchI8, tending to help'.to return; said "latch"to"'a'"posi- Lt'ion where fit'w'i'll engage and support the trunjni'o'n2 I. The lowefforward edgeof:ieaclf"latch I 8" is .providd'with" ashoiilderi'fi tobe engaged for releasing the'latchfash'ereinafterexplained.

.As shown in Figs. .2 and 3, 'thela'tches" tiliare interposedbe'tween"the""ifree.v end or .theu'earward door-1'2 and-"theadjacent:eridrmFMbeneath: a "guard. p1 ate" 2;! andaretdijsposd".vvholly' above fthe'iower edge of saidend-sillbr bumper;and also aboveth lowerj porti'ontfoithe'rear door inpro- ;tected positions. This.prevents"disarrangement I of theilatchesior acci'dental'finjuryith'ereto inf the :event of wreckage .ofithe 'car;:as*frequentiy :oc-"curs, thus'tinsuring adequate protection of "the latches'tomaintain-the same ini'prop'erf operative -po"s'itions.

One i form ii of 'ielectri'caliy actuated trippin'g mechanism is. shown"in "Eigs."2"to"7,' in "which however,"theltri'ppingi armfiis'mounted'ffor slid-- 'ing" movement to release eachofi thexlatches l 8whichsupport" the free-edge hf'the'door'i 1 2;

7The free edge "or the doorIIZ isfprovideidwith a shoulder 1 3I normally"disposed immediately "over 'ithe upper lend" of thetr ippingfa;rm "I32,as shown inFigZ a -isaid upbf 'r end'of the" tripping 4 adapted toenter the space between the door and the forward edge of the latch I8 tomove said latch to its released position, as shown in Fig. 4.

The tripping arm I32 is arranged vertically 5 and slidably mounted bymeans of rollers I 33 in 10 solenoid I 31; A coiled spring I38 acts onthe "plunger I36 tending to move the latter to an ex- #:tendedposition,asshown in Fig. 5.

Current is supplied to the solenoidl31 through aflvirteliififRoma-"gravity switch I39 which is jgu shown-asi'aizmercury switch. Theswitch I39 is "eonstructed in the usual manner of a tubular'fbodywoffinsulatingmaterial enclosing a pool of mercuric. and having apair of contacts at one "endp'ortion of the switch body which haveelectrical connection through the pool of mercury car until the latchingmeans is released for dump- V 'whenithe bodyrlis tilted-iimionedirectionmszshuwn 'linl i'gs'z3lande lrbuteareroutzoft electriealeconion l with achcoth'er 'wh'emthe switcliziisetiltdinsanotheridirectionIasrslititvninfi'ig.1J7.

I Thimercluliyisiiiitch I-ISBiissupportEdbyEamarm tee pivotallym-ountedonaa shaft iflafidprevidd with a counterweight- 1flwhibi'tinormallyractsito move the arml Hmtoiits loweredposition'yasvshuwn iull linesiim'Fig: 7,i:whereztthezeounterweight .1 rI 42 2 stops:theLfdownwam.swmgingim'ovementlhy thelan'gularportionzifizz'thereoi. ii'rhe sher MAI :i-s'supperted abeaningebox '14ipand .a'lsmhas mounted? thereon an :a'ctuatingearm at: l lii'which has-a shouldered: connectionfwith theiiarm Hi0,

so. as to "lifttthe latteriiarmr'irometh'e'izpositlon showna inEFF-igfi' 'htoithe position fshownzinim'gss ii 'and e, while theactuatingxarmi-MS s'irnevertheless free for movement'relativtotitheiarmflw to the: dottediline position:mfi Eig.1 7. :Z'Iheaarmflfl e *haslan"o'ii staridiri zioracket fiiconnected therewilth from whichiacounterweight 'lflaissusperided tozreturn the actuatingjza'mn flmmmzthefposition shown'f in "dotted ilinesizinisEig; II,to'i'thefiullrime zpositiorrtherein.

= when the -actuating arm ii isi-engagdzhvithe lug' fl on -the ibo'ttomof th'e' ear -sidesillfiarfd is moved thereby from the full linepositionin lil'g. 7, -which is its normal position asdescribed to theposition shown in -Fig. 3. ""l his cemse the poorer-mercury to' betiited into en'gag'emen with the contacts in the 's'vv itch,=' blosingtheelectmc circuit through the Wire-138 i'tci the@sb1enoid 1I1,'energizingg the' latter. IIhe oppositeiiside bfkm S'Wit'ch IBQ aridnofthe "so1eneidare connec d to '55 "any suitable oridesirable source ofelectriehl iiurrent sufii-cient to -actuate the sele'neid."i'rheienergizingof t-he' solenoid W31" retracts theiphmger 136 againstthe tension 'f the spring wee-wed "slides -the"trippingarmfli,iupwarkily; lid- 'ingmovementzofsaid 'trippinggrm-isstoppe by -7 theactuating arm, the counterweight I 42 i"tncns said arm-:to its normaluptightcposition: as shown in Figs-'1. "iihis imm'ediately breaks' itheeireiiit at the switch and deenergizes the solenoid fll, allowingthespring] 38 to move the tripping arm am- 132 isshown'assubstantially"-we'dge shaped 76 I32 to its lowered positiomiFigi )Fwhereifiis door.

It will be noted that the wedging enact the arm I32 is so slopedthatthere will be no tendency for the engagement thereof by the latchI8'to push the arm I32 downward against the force of the solenoid.Therefore, the only required function of the solenoid is to raise thetripping arm up to its operating position at the proper time, and topermit it to be lowered at the proper time,lwhere the latch hasbeenreleased and before the end-sill strikes the upper end of thetripping arm.

When the car moves over the tripping mechanism in the reverse direction,the lug 41 will engage the actuating arm I45 and. move it to the dottedline position in Fig. '7, but such movement is relative to the arm I40carrying the mercury switch, and therefore the circuit is not closedthrough the'switch. Thus the reverse movement of the car does not causea raising movement of the tripping arm I32.

- The design illustrated has provision for supporting the free edge ofthe door by two latches on respectively opposite sides of the centerline of the car, and each arranged for release by a solenoid-actuatedtripping arm. However, if desired, the construction may utilize onesolenoid for actuating two separate. tripping arms, and if two separatesolenoids be provided, both of those may be controlled from a singleswitch.

The circuit controller shown in Fig. 8 may be substituted for that shownin Fig. 3, if desired, or vice versa, inasmuch as each controls theoperatlonof a solenoid, and may be used to control the operation ofeither type of tripping arm.

It will be obvious also that the tripping arm may be actuatedpneumatically, instead of by the electrical solenoid, by connecting thepiston of a of the end sill structure and the bottom of thedoor.

that the latch hooks do not project below the bumper sill and areprotected between the bottom door and the bumper sill in such'fashionthat they will not be interfered with by obstructions on the track. Allof the different devices likewise provide for raising the unlatching armso that it will come'up to the point of engaging the hooks forunlatching at .the proper time and without contact with the normal dropbottom door and without possible contact with the end sill. The releaseof the unlatching mechanism always takes place in time to permit it todrop away from the latch hooks themselves immediately after these latchhooks have been rotated around the pivot far enough to release the latchhooks from their supporting engagement with the drop bottom door.

In the form shown in Fig. 8, a tripping arm 95 has a head 96 in positionto be moved into engagement with a forward face of thedoor supportinglatch I8b which normally supports, the free edge of the doorIZb by meansof a trunnion m, as described above. Thetripping arm .95 is All of thedifferent forms embody the feature pivotally supported at 91 on abracket 98, and has a counterweight 99 on the opposite end thereof fromthe head 96. This counterweight 99 reduces the amount of power requiredto'raise the tripping arm 95, but does not prevent it from fallingpromptly when released. 1

The tripping arm has a shoulder I00 in position for engagement by awedge I04 carried at the forward end of a member I02, slidably mountedupon rollers I03 within a guide member I04. The guide I04 has a .slotI05 in the under side thereof through which an arm I06 projects, whicharm is rigidly formed on the wedge member I02. The arm I06 is pivotallyconnected at I01 with a plunger I08 on an electrical solenoid I09. Acoiled spring H0 is sleeved over the plunger I08 and has a bearingengagement therewith at its outer end at III, tending to move the.plunger in an outer direction relative to the solenoid I09. 7

The solenoid is controlled by a switch which is actuated by ,a shoe 2 inposition for engagement with a lug 41b secured to the under face of theside sill of the car as described. The

shoe H2 is secured to a sleeve II3 slidably connected at H4 with arocker member H5 which is pivotally supported at MB.

A coiled spring I I1 is housed within the sleeve I I3 and tends toextend the shoe I.I2 relative .to the rocker member I I5. The rockermember I I5 is free to turn in a clockwise direction .in'Fig. 8 aboutthe pivot '6, but has its movement in the opposite direction limited byan arm I I8 adapted toengage a rigid stop I I9 mounted in a fixedposition beneath the track. A spring I20 is connected between the rockermember I I5 and a stationary anchor I2 I, tending to restore the rockermember and the shoe I I2 to a central position, as shown, if moved outof said position.

The sleeve I I3 has an arm I22 projecting laterally therefrom andsupporting a plunger I23 sliclably mounted therein through aninsulatingbushing I24. A coiled spring I25 tends to move the plunger 123in one direction. The free end of the plunger I23 carries a contact I26in position to engage a contact I21 secured to the rocker member H5 butinsulated therefrom. The contact I 21 is connected through a wire I28with the solenoid I09. The contact I26 and opposite side of the solenoidcoil may be connected with a track circuit, or other source ofelectrical supply through suitable connections as shown, adaptedtoenergize the solenoid upon the closing of the switch I26I2'I.

When the shoe H2 is engaged by the lug 41b and depressed, this willclose the contacts I26, I21, sufficiently to energize the solenoid I09.When the solenoid is thus energized, the plunger I08 is moved to theright in Fig. 8, thereby moving the wedge I M to its dotted lineposition, pressing upward on the shoulder I00 and raising the trippingarm 95 to the dotted line position illustrated. This moves the head 96in position to engage the forward face of the latch I81) upon v furtherforward movement of the car to release the door for dropping. As soon asthe lug 41b passes over the shoe H2 the latter is raised by the spring II! disengaging the contacts I26, I21, which causes deenergizing of thesolenoid coil I09. This allows the spring I I0 to move the Wedge I0=Iback to the full line position, and allowing the tripping arm 5 to belowered out of the path of the latch I82), and the end sill of the car,for dumping of the doors in the manner desc i d a e.

when the car moves over. theadumpingjbin .and

the tripping mechanism in .a reverse direction (toward the right .inFig. 28).,=the shoe zlzl2i'will' be .rotatedtoward the right bysth'eengagement of the lug 41b. The switch will :rotate with the shoe sinceit is carried by :therocker member 1:15.

and will not be closedbyrthis rotary..movement becauseof thelackofmovementlof the shoe H2 and its. sleeve ll.3':relative totherocker member H 5. Thus the. solenoid vH39 :Will .not the energizedto raise the tripping arm .35. After 'the-ca-r-tth-us. passes over thetripping mechanism. in the reversedirection described,- the spring Iwill :return the shoe H2 to its vertical position, where-:it-is heldbythe stop l H). 7

As described above, oneor more latches may be used for supporting the:free edge ofthe door, and, if desired, the tripping arm 95 maybeprovided for each latch. Gne solenoid could be-used,

if desired, to operate several tripping arms which correspond with therespective latches, or separate solenoids provided for therespective'trip ping arms, all of which may be controlled from a singleswitch orshoe.

I claim:

1. In conveying mechanism, the combination.

with a trackway, a dumping vehicle mounted on the trackway andincluding-a frame-structure having a drop bottom dumping door,-and latchmeans for holding the door closedand movable to release said doorfor'dropping o-f tripping mechanism mounted at the trackwayfor upwardmovement relative theretoin position -to-actuate the latch means, saidtripping mechanism including an actuating armhaving an end-portion inposition for engaging the latchmeansto release :the same, meansmounting-said tripping arm for sliding movement, electro-magnet-ic meansfor actuating said arm, switch means -forcontrolling saidelectro-magnetic means, and swinga-ble means actuated in-responseto.movernent of the dumping vehicle to apredetermined position foroperating said switch means;

2;.In conveying mechanism, latchtripping" mechanism adapted to bemounted ata track- Way to release latch mean's of a drop'b'cttom door,said latch tripping mechanismcomprising atripping member, means mountingsaid member fortro-magnetic means,and swingable means'adapted to beactuatedby movement of a vehicle-along the trackway for operating saidswitch -means;

'3. In conveying mechanism,--thecombination with a trackway, adumpingconveyance "movable along the trackway and'including a framestructure having transverse-end-sil-l structure-and having a lading bodywith a drop bottom-=door,

veyance, of tripping mechanism including means' mounted at the trackwayandmovable to-release' the latch means, electrically actuated meansoperatively connected with the latch release-means for.movingihe:latch'tripping. mechanism ;to=-en-. gaging position, andmeans actuated in response.-

tomovementrof the dumping conveyance torazpredeterminedrpositionionwthe.trackway-for controlling engaging of: :the. electrically-actuated means.

.41.;Inconveyingalmeohanism, the combination:

withsagtraokwayya, dumping conveyance movable alon'gzthe :trackwaylandincluding .aframe. struce tur'eahavingatransverse. end-sill structure,and; having..;.a aladingbodyzwith a..drop bottom "door; latch-means:ifor holding the door in c'losed posi:

tion and movable to release the door for opening, said-latch :meansbeing :located wholly above I the lowestcportion" of. the end-sill.:structure in the:

same longitudinal rvertical plane. of :the conveyanon, eof-'tripping..imechanismincluding 'means mounted. at .the. track-wayandmovable to release.

the-.;.lateh :means, electrically actuated means vmounted:atrthetrackwayin :positi'onuto begd-is.

posed-directly undertthe-drop bottom. door when the dumping conveyancepassesxthereoversand.

connected WithiSdid latch:relea's ermeanssfor moving;;.thelatch-tripping :mechanism to. engaging position,. (and means forcontrolling "the :action or the :-;e1ectrically-actuated means; andoperated by thermovement of z the dumping; conveyance thereoven;5:111conveying mechanism; the combination wit-ha trackway aidumpingsconveyance-movable along the trac'lewayrandincluding.rasfram-e-struoturcrhaving transverse:endesillstmcture andhaving; a .ladingbody .with-za'drop "bottom door, latch" means.forszholdingl: :thQidflOI' in closed position it and: .movabletorelease the. door. for opening, .of

tripping mechanism :including. means mounted at :thetraokwayand movableinto operatingrrelation with, the Jatchrmeans, andreleotro-magneticmeans mounted attt-he ,trackway imposition :to be disposed: directly,under the'rdrop bottom: door when the; dumping-conveyance is :rpassing-th"ere- J over: and .oneratively. connected-with the 'tI'iIJ- pingmeansforymoving said tripping -.means into operativerelatiomrwith lithelatch; means to. reeafic-rrtheedoor; and means; for zzontrolling. the

actiona-of the -electroamagnetic mean's and op.-'

erated by the movement zo'f the dumping conveyancethereover.

i6l' Int-conveying:mechanism, the. combination with a'itrackway,agdmnpingcconveyance movable along the trackway and including a framestructluichayingttransverse endsillstructureand havingailatiinglrbodyswith-a .drop.:.bottom door, latch meansifor holding thedoor in-clos'edpositionand movable 1120. release the zdoor for opening,.said

latclrmeans:beingilocated wholly aboveithelowest DortionpfZthfirifll'lidrfifllitlllfltlfl' inthelsame {Ion--giitudinal;verticalizplane zofithjel-conveyance, of trinping::.mechanism,i-rrcluding. T means mounted at 'ithelwtrackway iandimovablefintoaactuating en-' gagement with'ihe datchzmeans, electro-magneticmeansconnected iwithisai'dlatch actuating means fiommovingzth'eilatchactuatingmeans .to engag;

ingrpositi'on; andar'rreans actuated in response/to movement zof..afdumping. conveyance 'ior. icontrol'ling the eleotroemagneticmieans;

1'7... Fln gconveying :;mechanism,. the combinationwith axtrackway,adumpingrconveyance movabl v tion and movablaftoreleasegthe 'doorfor-openingy oi tripping meohanismeinoluding means mounted at thetrachwayiand-movable into operating relation with the latch means,electro-magnetic means for moving said tripping means into operativerelation with the latch means to release the door and a switchelectrically connected with said electro-magnetic means and havingoperating means therefor in position for operation by the movement ofthe dumping conveyance along the trackway to a predetermined positionrelative thereto.

8. In conveying mechanism, the combination with a trackway, a dumpingconveyance movablealong the trackway and including a frame structurehaving transverse end-sill structure and having a lading body with adrop bottom door, latch means for holding the door'in closed positionand movable to release the door for opening, of tripping mechanismincluding means mounted at the trackway and movable into operatingrelation with the latch means, power'means constructed foroperation by asource of power externally of the conveyance itself and mounted at'thetrackway for moving the tripping means into operative relation with thelatch means causing release of the door for dropping, and meansforcontrolling the action of said power means and operated by the movementof the dumping conveyance to a predetermined position in the trackway.

9. In conveying mechanism, the combination with atrackway, a dumpingconveyance movable along the trackway and including a frame structurehaving transverse end-sill structure and having a lading body with adrop bottom door, latch means for holding the door in closed positionand movable to release the door ior opening, of tripping mechanismincluding means mounted at the trackway and movable into operatingrelation with the latch means, power means constructed for operation bya source of power externally of the conveyance itself and mounted at thetrackway for moving the tripping means into operative relation with thelatch means causing release of the door for. dropping, and meansactuated in response tomovement of the dumping conveyance to apredetermined position on the trackway for controlling said actuation ofthe power means.

10. In conveying mechanism, the combination with a. trackway, a dumpingconveyance movable along the trackway and including a frame structurehaving transverse end-sill structure and having a lading body with adrop bottom door, latch means for holding the door in closed positionand movable to release the door for opening, said latch means beinglocated wholly above the lowest portion of the end-sill structure in thesame longitudinal vertical plane of the conveyance, of trippingmechanism including means mounted at the trackway and movable to releasethe latch means, electrically actuated means for moving the latchtripping mechanism to engaging position, and means actuated in responseto movement of the dumping conveyance to a predetermined position on thetrackway for causing energizing of said electrically actuated means andmovement of said latch tripping mechanism.

11. In conveying mechanism, the combination with a trackway adapted toreceive thereon a dumping conveyance for movement along the trackway andhaving a drop bottom door with latch means for holding the door closedand movable to release the door for dropping, of tripping mechanismincluding means mounted at the trackway for movement into operativerelation with the latch means to release said latch means,

and electro-magnetic means connected with the latch tripping means formoving the tripping means into said operating position, and a. switchelectrically connected with said electro-magnetic means and havingoperating means therefor in position for operation by the movement ofthe dumping conveyance along the trackway to a predetermined positionrelative thereto.

12. In conveying mechanism, the combination with a trackway adapted toreceive thereon a dumping conveyance for movement along the trackway andhaving a drop bottom door with latch means for holding the door closedand movable to release the door for dropping, of tripping mechanismincluding means mountedat the trackway for movement into operativerelation with the latch means to release said latch means, andelectro-magnetic means connected with the latch tripping means. formoving the tripping means into said operating position, and means inposition for actuation in response to movement of the dumpingconveyanceto a predetermined position on the trackwayfor causing said actuation ofthe electro-magnetic means.

.13. In conveying mechanism, the combination with a trackway adapted toreceive thereon a dumping conveyancefor movement along the trackway andhaving a drop bottom door with latch means for holding the door closedand movable to release the door for dropping, of tripping mechanismincluding means mounted at the trackway for movement into operativerelation with the latch means to release said latch means, power meansconstructed for operation .by .a source of power externally of theconveyance itself mounted at the trackway connected with the latchtripping means, for causing said movement of the tripping means to alatch releasing position, and means for controlling the action of saidpower means and operated by the movement of the dumping conveyance to apredetermined position in the trackway. H

14. In conveying mechanism, the combination with a trackway adapted toreceive thereon a dumping conveyance for movement alongthe trackway andhaving a drop'bottom door with latch means for holding the door closedand movable to release the door for dropping, of tripping mechanismincluding means mounted at the trackway for movement into operativerelation with the latch means to release said latch means, and powermeans mounted at the trackway connected with the latch tripping means,for causing said movement of the tripping means to a latch releasingposition, and means mounted at the trackway in position for actuation bythe dumping conveyance when moved to a predetermined position on thetrackway for controlling said actuation of the power means.

15. In conveying mechanism, the combination with a trackway, a, dumpingconveyance movable along the trackway and including a frame structurehaving transverse end-sill structure and having a lading body with adrop bottom door, latch means for holding the door in closed positionand movable to release the door for opening, of tripping mechanismincluding means mounted at the trackway and movable into operatingrelation with the latch means, and power means mounted at the trackwayoperatively connected with said movable means for moving the trippingmeans into operative relation with the latch means causing release ofthe door for dropping, and means actuated by the dumping conveyance inresponse to movement of the tripping meehanism including means mountedat t'lie"traokway I and movable; to. release the latch =means,electrically actuated meansoperatively 'conneoted'-Withsaid movablemeansfor moving I the latch tripping mechanism; to: engaging position,--and means mounted for-swinging: movement lengthwise: of; the trackway-and constructed for V circuit: closing action upon movement'in onedirection only relative thereto-1andiactuatedl by thedumping-conveyance: in; responseto .movement off the: dumpingconveyance. to: a. predetermined 1 position on: the .trackway; saidcircuit .olosing means: bein g v electrically connected. .wvitlrthe:electrically actuatedfmeans for: causing energizing: of said:electrically. actuated tmeans and. movement oi'lsai'dlatchtrippinamechanismaupon:saidzmorvement; of. thez'sald circuit:closing; me ans.

:17; i Inrconveying: mechanism; the: combination of atnaokwayadaptedtoreceive th'ereonia dumping conveyance for movement along the :trackwayand havinmardropbottom door' latch means: for holding thei'doort closedand movable to release the door foridroppin'g', tripping mechanismiincludingmeans mounted. at. the trackway "formovement: into -operativerelation with? the a latch means to release said latcl'r m'eans,electromagnetic means operatively-xconnected with said tripping meansforzmoving the. tripping, means intosaidi operating position; and meansin posi- 1 tion'; for: actuation by; the-:dumping conveyance fim'response to movement of the cluinping? convey- Number" V ancerinvonedirectionronly toaipredeterminedzposition: on; the: trackwayfionrcausingsaid-actuation of: the ..electro-magnetic'means.

18. 'In. conveyingcmechanism;theecombination of at-rackwayaadaptedto-receivathereonia.dumping": conveyance. tor;movement; along the trackwayand having. a dro bottom: doorwit'h. latchmeans for holding-the door closeda-nd-movable to release the door fordropping, trippingfimechanismincluding. means, mounted: at; thentnackwayfor. movement into operative relation; with; the

latch means -,t0"'1:e1ease latch; meansyaand power means. mounted at:the trackwayr'andzxoperatively connected'ewithp saidlatohreleaseimeansfor causing saidpmovement;of:.the-trippingrmeans toalatch releasingposition, andmeansamountd at the trackway: in position: for actuation:by'the dumping: conveyance when: moved? in ,oneasdirection only to. apredetermined:rposition'onazthe trackvvay for-causing? said; actuationof, the power means. l l GH- W. -SANFQRD;

. V ,REEERENCES ormn The followingreferencesare "of''- record in" thefile of this-patentr r UNITED STATES PATENTS.

